Nikolai Nikolaevich Kolomeitsev, also spelt Kolomeytsev (Russian: Николай Николаевич Коломейцев) (16 July 1867 (near Kherson, Ukraine) - 1944 in Paris) was a Russian naval officer and explorer of the Arctic.

Nikolai Kolomeitsev was born in the village of Pokrovka near Kherson in Ukraine (then part of the Russian Empire) in 1867. He entered military service in 1884 and graduated as an officer of the Imperial Russian Navy in 1887. He was promoted to lieutenant in December 1893. In 1894-1895, he was assigned to the Russian Pacific Fleet, and after graduating from mine warfare school, served on several vessels operating in Siberia.

Kolomeitsev became a member of the Chief Hydrographic Administration’s Survey Expedition to the White Sea. He also took part in an expedition to the Yenisei Gulf led by L. Dobrotvorskiy, which gave him expertise on sailing in arctic waters.

In 1900, Baron Eduard Toll led an expedition on behalf of the Russian Academy of Sciences on ship Zarya. Kolomeitsev was named commander of the ship during the expedition. His second-in-command was Fyodor Andreyevich Matisen, who had taken part in an expedition to Svalbard. Alexander Kolchak also accompanied the expedition as third naval officer and hydrographer. All these officers were from military backgrounds. The expedition was known as The Russian Polar Expedition. Its aim was to explore well the area north of the New Siberian Islands and eventually sail towards the North Pole in order to find the elusive Sannikov Land.